Raft Foundation Modification .... Please help!!!

[5teves]

Hello All,

I'd really appreciate all of your expert advice in regards to the best solution for this project.

Many years ago we had a brick shed built at the best of the garden. The builder had chosen to build It on a concrete slab instead of a strip foundation.

The problem we have now is that, we wish to landscape out garden. Which will involve striping away quite a lot of oversite soil in order to bring the garden ground to one level so that it's in line with the house floor level.

As you've probably guessed, because the garden was slopping upwards away from the back of the house, the floor level of the shed would result in being about 40cm higher then the new garden floor level.

We don't really want steps going upto to it, unless it's the last resort.

The question is, is there anyway we can safely bring the floor level of the shed down to match the new ground level of the garden?

We anticipate this will involve quite a lot of work if it's at all possible in the first place, however its a decsion we can make once we know what the options are.

Again, I'd appreciate all of your advice. Thanks in advice.

 

[IT Minion]

Have you thought about leaving your shed standing tall where it is and having a retaining wall in front of it?

I'm not a builder but my guess is that otherwise you're going to have to tear the shed down, demolish and dispose of the foundation then redo the foundation and start again.

 

[^woody^]

The question is, is there anyway we can safely bring the floor level of the shed down to match the new ground level of the garden?

No.

 

[5teves]

Have you thought about leaving your she'd standing tall where it is and having a retaining wall in front of it?

I'm not a builder but my guess is that otherwise you're going to have to the the shed down, demolish and dispose of the foundation then redo the foundation and start again.

Hi, yes that's a solution if we keep the floor level as it is. We were hoping that to be able to get the desired outcome by making some alteration.

Tearing it down would definatley not be worth doing, so not a option.

 

[5teves]

No.

Hi Woody,

Thank you also for your reply.

Would under pinning the walls not work?

Say if we dug beneath all four walls and poured concrete in, so that walls sit directly onto on top.
Will that then not allow for the raft slab to be cut away?

 

[^woody^]

Hi Woody,

Thank you also for your reply.

Would under pinning the walls not work?

Say if we dug beneath all four walls and poured concrete in, so that walls sit directly onto on top.
Will that then not allow for the raft slab to be cut away?

Yes but it's a major task.

New foundations would need to be down to suitable depths taking into account ground condition and any nearby trees or large shrubs. Plus a factor to allow for underpinning a whole building and it not then experiencing differential settlement.